Medium-Term Outcomes of the Different Antithrombotic Regimens After Transcatheter Aortic Valve Implantation

Abstract

Bioprosthetic valve thrombosis is associated with accelerated bioprosthesis degeneration and valve re-replacement. Whether 3-month warfarin use after transcatheter aortic valve implantation (TAVI) protects against such consequences is unknown. We aimed to investigate if 3-month warfarin treatment after TAVI is associated with better outcomes than dual antiplatelet therapy (DAPT) and single antiplatelet therapy (SAPT) at medium-term follow-up. Adults who underwent TAVI were identified retrospectively (n = 1,501) and classified into warfarin, DAPT, and SAPT groups based on antithrombotic regimen received. Patients with atrial fibrillation were excluded. Outcomes and valve hemodynamics were compared between the groups. Annualized change from baseline in mean gradients and effective orifice area at last follow-up echocardiography was calculated. Overall, 844 patients were included (mean age: 80 ± 9 years, 43% women; 633 receiving warfarin, 164 DAPT, and 47 SAPT). Median time to follow-up was 2.5 (interquartile range 1.2 to 3.9) years. There were no differences in the adjusted outcome end points of ischemic stroke, death, valve re-replacement/intervention, structural valve degeneration, or their composite end point at follow-up. Annualized change in aortic valve area was significantly higher in DAPT (−0.11 [0.19] cm2/year) than warfarin (−0.06 [0.25] cm2/y, p = 0.03), but annualized change in mean gradients was not different (p >0.05). In conclusion, antithrombotic regimen, including warfarin, after TAVI was associated with marginally lower decrease in aortic valve area but no difference in medium-term clinical outcomes compared with DAPT and SAPT. Bioprosthetic valve thrombosis is associated with accelerated bioprosthesis degeneration and valve re-replacement. Whether 3-month warfarin use after transcatheter aortic valve implantation (TAVI) protects against such consequences is unknown. We aimed to investigate if 3-month warfarin treatment after TAVI is associated with better outcomes than dual antiplatelet therapy (DAPT) and single antiplatelet therapy (SAPT) at medium-term follow-up. Adults who underwent TAVI were identified retrospectively (n = 1,501) and classified into warfarin, DAPT, and SAPT groups based on antithrombotic regimen received. Patients with atrial fibrillation were excluded. Outcomes and valve hemodynamics were compared between the groups. Annualized change from baseline in mean gradients and effective orifice area at last follow-up echocardiography was calculated. Overall, 844 patients were included (mean age: 80 ± 9 years, 43% women; 633 receiving warfarin, 164 DAPT, and 47 SAPT). Median time to follow-up was 2.5 (interquartile range 1.2 to 3.9) years. There were no differences in the adjusted outcome end points of ischemic stroke, death, valve re-replacement/intervention, structural valve degeneration, or their composite end point at follow-up. Annualized change in aortic valve area was significantly higher in DAPT (−0.11 [0.19] cm2/year) than warfarin (−0.06 [0.25] cm2/y, p = 0.03), but annualized change in mean gradients was not different (p >0.05). In conclusion, antithrombotic regimen, including warfarin, after TAVI was associated with marginally lower decrease in aortic valve area but no difference in medium-term clinical outcomes compared with DAPT and SAPT.